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2005Ikegami-Obs-Enha Observation of enormously enhanced nuclear fusion in metallic Li liquid H lkegami R Pettersson L Einarsson Rapporterna kan bestallas frin Studsvikbiblioteket, 6 11 82 Nykoping. Tel0155-22 10 84. Fax 0155-26 30 44 Statens energimyndighet e-post [email protected] Box 3 10, 63 1 04 Eskilstuna Observation of enormously enhanced nuclear fusion in metallic Li liquid Fiirfattare: Hidetsugu Ikegami Hibariga-oka 2- 12-50, Takarazuka, Japan Dep of Analytical Chemistry, Uppsala University Roland Pettersson Dep of Analytical Chemistry, Uppsala University Lars Einarsson The Svedberg Laboratory, Uppsala University RAPPORT INOM OM~DETENERGIFORSKNING ALLMANT Rapportnummer: EFA 0512 Projektledare: Roland Pettersson Projektnummer : P2062 8 - 1 Projekthandlaggare pi Statens Energimyndighet: Lars TegnCr Box 310 -631 04 Esk~lstuna. Besoksadress Kungsgatan 43 Telefon 016-54420 00 . Telefax 016-54420 99 stem@stem se .www stemse Org nr 202100-5000 Observation of enormously enhanced nuclear fusion in metallic Li liquid Hidetsugu Ikegami * +, Roland Pettersson + & Lars ~inarsson* * Hibariga-oka 2-1 2-50, Takarazuka 665-0805, Japan + Department of Analytical Chemistry, Uppsala University, Box 599, SE-751 24 Uppsala, Sweden * The Svedberg Laboratory, Uppsala University, Box 533, SE-75121, Uppsala, Sweden Deuterons of some tens keV energy have been implanted on a surface of metallic Li liquid. Alpha particles produced in the fusion reaction 'Li + d + 8~e+ n + 201 + n were identified using Si surface barrier detectors (SSD) and thin foil energy loss method. The rate of alpha particles was up to one million per second at 1 pA of deuterons. This is a factor of 1010 - 1015 higher than what is expected based on available nuclear-reaction cross sections l. Since we do not observe any alpha particles when the Li sample is solid at room temperature the enhancement must be connected with the macroscopic scale correlation in the liquid 2 - 4. The alpha- particles spectrum exhibits a broad peak at the energy of full Q-value of 15.1 MeV of the reaction. Energy loss measurements show that this peak is actually a sum peak of unidirectionally emitted paired a-particles each having 7.56 MeV kinetic energy and their momentum deficit must be covered by bulk liquid Li atoms. This indicates also the macroscopic scale correlation 39 4. Nuclei dressed with electronic configurations reveal dynarnical features influenced by their surroundings in some cases such as P-decay through capture of atomic electrons, internal electron conversion in nuclear isomeric transitions and so on. In these nuclear processes, penetration effects have been well known for atomic electrons which interact with nucleons inside nuclei. This would be also the case where low energy nuclei undergo fusion reactions under an electron background to suppress nuclear Coulombic repulsive force 2. In fact enhancement of the rate of nuclear fusion reactions by a factor of some 10 - 30 orders of magnitude has been anticipated in ultra-dense liquids in white- dwarf supernova progenitors 5. This enhancement is, however, common to entropy producing irreversible processes in liquids 2 - 49 6. The well known examples are the Henry's law on the solubility of gases in liquids and the Arrhenius'rate equation for irreversible (AGr < 0) chemical reactions in dilute solutions - 4. Here AGr denotes the Gibbs'energy (chemical potential) change in the reactions. General speaking the rate of irreversible reactions is exactly proportional to the rate of entropy increase. This general thermodynamic relation is strictly independent of nature of microscopic interparticle interactions 394. These considerations lead to the enhanced nuclear fusion reaction induced by slow deuterons (Ed< 1 10 keV) implanted in metallic Li liquid 29 43 7. 7Li+2H + 8Be+n + 24He+n+ 15.12Me~ (1) In this scheme the liquid consisting of Li ions immersed in a sea of mobile s-electrons takes the parts of solvent reacting with solute deuterons. Orbital electrons of Li ions or atoms are able to adjust electronic state so as to link the atomic fusion process with the nuclear fusion because they gyrate more rapidly than deuteron speed 4. In the linked irreversible atomic fusion process Li+H +Be (2) macroscopically distinct parts of the liquid are correlated and long-range coherence appears 33 43 6. These aspects are reflected in the rate of linked atomic and nuclear fusion reactions in the form of Arrhenius 'equation k(T) = ko exp (- -] 9 AG,< 0 enhancement of reaction rate expected. Faint beam density operation was found to be useful to avoid the local temperature rise of the Li metal surface due to the non-linear thermal effect 1. For instance, a temperature rise of 190 " C above the melting point of Li metal results in a quenching of the enhancement as much as a factor of 104 as seen in equation (6). In order to match with these requirements a compact ion source of PIG type equipped with permanent magnets was made, which produced ion beams with several tens of pA fiom 1 keV to 35 key. A beam of typically 10 pA was extracted fiom a slit with a hole of 1 mm in diameter and then accelerated after passing through a molecular ion and neutral beam filter system. A faint deuteron beam in the range from a hundred to several nA entered target chamber was implanted vertically on a surface of metallic Li target of 19 mm in diameter and the amounts of about 1 g. The currents of collimator and target were monitored during experiments. The product charged particles from the target were observed using a 300 ym thick Si surface barrier detector (SSD) positioned at the angle 8 lab = 115 " with the effective acceptance angle of 0.06 % of 4 n: steradian. The fkont face of SSD was covered with a 5.5 pm thick A1 foil to prevent &rays and scattered deuterons from hitting the detectors. A movable A1 foil was introduced in front of SSD in order to measure the energy loss characteristics of the particles. Throughout the experiments detector output pulses and spectra were monitored comparing with those of a- particles from a calibration source of 241Arn (5.48 MeV) mounted near the Li target. Slow neutrons (En = 2Ed = 20 - 60 keV) emitted fiom the target were monitored using a BF3 rem-counter covered with a polyetyrene and boron mixed plastic case of about 100 mm thickness. The experiments were carried out for metallic Li targets in both liquid - and solid - phases for cornparasion. In the solid phase at room temperature no event was observed in either case of charged particle and neutron measurements. This fact was consistent with the very faint nuclear hsion probability evaluated by equation (5). In any case of liquid phase of bulk Li metal or local melting Li surface, a broad peak was observed in the charged particle energy spectra. The observed enormous rate enhancement was, thanks to improvements mentioned above, reproducible and consistent with previous results. It was as reported dramatically dependent on the state of liquid Li surface 4. Typical examples of spectra are seen where kg is the Boltzmann constant 2. The factor ko is expressed as ko = 11, N2 0 (Ed) (4) where 11, N2 and o(Ed) are number current of iniplanted deuterons with an acceleration energy Ed , surface number density of Li ions or atoms and nuclear fusion cross-section, respectively. If there is no correlation in the liquid at all, the rate is k(T) = ko and almost all implanted deuterons undergo stopping within the depth of a few hundredth pm on the surface of liquid without fusion reaction. Because the intrinsic probability of nuclear fusion is very faint typically 4 x 10-23 at Ed = 10 keV and 8 x 10-18 at Ed = 20 keV 29 4, 7. However under the presence of macroscopic scale correlation the linked fusion reactions are dominated by the Gibbs energy change AG, in equation (2). In the present fusion scheme the value of AGr has been derived to be around -1.35 eV from the bond energy of metallic Li liquid. This results in the enormous enhancement in equation (3) exp (- $)= 5 x 1013 just above the melting point of Li metal T = 460 K 2. The predicted enhancement in equation (6)was fully verified in the previous experiment 1. Observed enhancement was a factor of some 1015 - 1010 depending on the deuteron energy Ed = 10 - 24 keV. Furthermore an additional event suggesting the strong correlation in bulk liquid Li atoms was found in the observed a-particle spectra. The aim of present experiment is to confirm the enhancement and also to investigate the correlation aspects of Li liquid. The present experiment is a natural extension of the previous work 1 and using an improved machine which is constructed for low D2 gas consumption to diminish LiD formation on the liquid Li surface during experiments. Special attention was paid to generate clean and stable deuteron beam but of faint intensity because of the huge 1. Ikegami, H. & Pettersson, R. Evidence of enhanced nuclear fusion. Bulletin of Institute of Chemistry (Uppsala University, September 2002). (http://www.inst.kemi.uu.se/Bulletin/Bulletinenl .pdf). 2. Ikegami, H. Buffer energy nuclear fusion. Jpn. J. Appl. Phys. 40, 6092-6098 (2001). See also No. 1 paper in ref. 1. 3. Kondepudi, D. & Prigogine, I. Modem Thermodynamics. (John Wiley & Sons Ltd., Chichester, 1998). 4. Ikegami, H. Long-range coherence revealed in entropy enhanced chemo-nuclear fusion. Nature (submitted). 5. Schatzman, E. mite Dwarfs. (North-Holland, Amsterdam, 1958). 6. Widom, B.J. Some topics in the theory of fluids. Chem. Phys. 39, 2808-2812 (1963). - 7. Ikegami, H. & Pettersson, R. Recoilless non-thermal nuclear fusion. Bulletin of Institute of Chemistry (Uppsala University, September 2002).
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